Great improvement over electrochemical performance of zinc electrodes from sonochemical growth of cerium conversion films on zinc powder

The corrosion and dendritic growth of zinc electrodes are main reasons why zinc-based batteries have not been commercialized extensively. This work focuses upon the growth of cerium conversion films on modified zinc powder using ultrasonic immersion technique to obtain novel electrode materials for reducing the issues of zinc electrodes. Simultaneously, the surface state of conversion films and trace yields of Ce element imposing various concentrations of immersion solutions are evaluated. It is found that the yields of Ce element can be controlled by varying the concentrations of initial Ce(NO3)(3) solutions due to the dependence of conversion rate on the concentration of Ce(NO3)(3) solution. Moreover, the cerium conversion layers formed on zinc powder make significant contributions to suppress corrosion and dendritic formation of zinc electrodes. In particular, the cerium conversion films obtained with 0.0306 mol L-1 Ce(NO3)(3) solution provide the strongest inhibition capability in corrosion and dentritic growth. This is attributed to the surface characteristics of conversion layers with the effective formation of Ce-rich particles on the defect sites of zinc powder. (c) 2008 Elsevier B.V. All rights reserved.